The present invention pertains to vacuum encapsulated microstructure devices. It particularly pertains to the vacuum seal of a cavity between two wafers, and more particularly to the fabrication of such two wafers having a plugable hole for evacuation of gases from the cavity.
Various devices, such as microstructure infrared (IR) devices, require vacuum encapsulation for optimal performance. Conventional vacuum packaging is complex and costly. Known prior art approaches to wafer level vacuum sealing cannot yield adequately low pressures, the best in the range of 0.5 torr. Such pressures resulted in 50 percent signal losses for thermoelectric (TE) devices as an example.